Setting Breakpoints on Code That Has Not Yet Been
Loaded by the JVM Software

To set a stop breakpoint on a Java method in a class file that has not
been loaded by the JVM software, use the full name of the class with a stop
in command, or the class name with a stop inmethod command.
See the following example.

To set a stop breakpoint on a C function or C++ function in a shared
library that has not been loaded by the JVM software, preload the symbol table
of the shared library before setting the breakpoint. For example, if you have
a library named mylibrary.so that contains a function named myfunc, you could preload the library and set a breakpoint on the
function as follows:

(dbx) loadobject -load fullpathto/mylibrary.so
(dbx> stop in myfunc

You can also load the symbol tables of all dynamically loaded shared
objects by running your application once before beginning to debug it with dbx.